The term “atomizer” as used herein in the specification and claims refers collectively to a device capable of emitting a fine mist of liquid. Such devices are often referred to in the art also as foggers, sprayers, mist devices, humidifiers, rooting etc.
Atomizers used in agriculture and for domestic purposes serve for conditioning the environment both by increasing humidity such as in greenhouses and tropical gardens, for irrigation and for cooling. A variety of atomizers are known, referred to as rotary-cup atomizers, air blast/air assist etc. The present invention is concerned with pressure atomizers.
Cooling by atomized liquid is obtained by forcing a liquid, typically water, through specially designed nozzles so as to obtain a fog of ultra fine water droplets. The liquid droplets absorb heat energy of the environment and evaporate, whereby the energy (heat) consumed for converting the liquid into gas (vapor) is extracted from the environment, thus cooling the air.
The amount of moisture in the air divided by the maximum amount of moisture there could be absorbed at the same temperature (relative humidity) is a significant parameter in determining cooling potential. The lower the relative humidity, the more liquid can be vaporized, thus the more heat can be removed from the environment. Evaporative cooling can be used in most geographical zones owing to the fact that when temperature reaches its peak during day, relative humidity is normally at its lowest. For this reason, evaporative cooling is commonly used in many zones over the world.
Liquid atomizers are at times, used also as frost protectors by creating a mist layer above the agricultural growth, thus preventing frost from damaging the crops.
Pressure atomizers are commonly in use and typically comprise a housing fitted with at least one outlet nozzle, a core member associated with each nozzle for generating a vortex (often referred to in the art as “swirl”) and a strainer/washer member packed together by screw coupling of the nozzle to the housing. The atomized spray is obtained by guiding a liquid jet through a path causing the jet to swirl and upon exiting through a fine outlet nozzle, an atomized spray is emitted.
Typically, each outlet nozzle is associated with a single housing and where covering a large area with mist is required, thus several such housing may be mounted on a splitting element, each such outlet nozzle being directed to a different direction and said splitting element being connected in turn to a liquid supply line.